The subject invention relates to lightweight structural panels, and specifically, to lightweight panels suitable for outdoor use. It is desirable in the construction industry to have structural panels which while being lightweight and relatively inexpensive to manufacture, are also durable and suitable for outdoor use. For example, it is desirable to provide lightweight structural panels which may be used by homeowners to build additional rooms onto a house. It will be appreciated that panels which are lightweight, relatively inexpensive, and have high insulation qualities would have great appeal for such use. Other desirable uses for the lightweight panels of the subject invention would be as a house siding or roof material. Unfortunately, known lightweight panels are not suitable for outdoor use. They tend to become deformed, and crack, split, or harden when exposed to sun and weather forces.
Accordingly, it is an object of the subject invention to provide a structural panel which while being lightweight and relatively inexpensive to manufacture is also durable and suitable for outdoor use.
It is a further object of the subject invention to provide a structural panel having the above characteristics which also has high insulation quality.